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The origin of the recently reported chemical shift changes of backbone amide nitrogens of redox proteins upon redox state changes has been investigated. These effects are particularly marked in cytochromes and are clearly present after correction for pseudocontact shifts in the oxidized form (Boyd J, Dobson CM, Morar AS, Williams RJP, Pielak GJ (1999) J Am Chem Soc 121:9247-9248; Guiles RD, Basus VJ, Sarma S, Malpure S, Fox KM, Kuntz ID, Waskell L (1993) Biochemistry 32:8329-8340). 15N-HSQC experiments have been performed on both oxidized and reduced forms of cytochrome b5 in the absence and in the presence of 2 M guanidinium chloride (GdmCl). GdmCl in this concentration is known to sizably alter the structure of the oxidized form of the protein and, in particular, to perturb the hydrogen bonding network. However, the perturbation of the 15N-NMR chemical shift changes is minor compared to the changes occurring upon reduction. It is concluded that changes in hydrogen bonding upon reduction must be modest and cannot account for the observed chemical shift effects. Alternative explanations should thus be looked for.  相似文献   
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There is growing concern about mitigation-driven translocations that move animals from anthropogenic threats at donor sites because of their failure rate and lack of application of scientific principles and best practice. We reviewed all known lizard translocations in New Zealand between 1988 and 2013 and identified 85 translocations of 30 lizard taxa to 46 release sites. Most translocations (62%) were motivated by conservation goals for the species or the release site, and one-third were mitigation-driven translocations, typically motivated by habitat loss due to development. Mitigation-driven translocations began in 2003, and since that time have equalled the number of conservation-motivated translocations. Conservation-motivated translocations usually released lizards on islands without mammalian predators, whereas mitigation-driven translocations usually relocated lizards to mainland sites with introduced predators. Long-term monitoring has been sparse and often rudimentary. Eight lizard translocations have recorded population growth, including one mitigation-driven translocation that was into a fenced reserve. Research on commonly used management techniques to mitigate human-related impacts is recommended to establish whether these techniques benefit lizards in the long term.  相似文献   
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We structurally characterized the adducts of the catalytic domain of matrix metalloproteinase-3 (MMP3) with three different nonpeptidic inhibitors by solving the solution structure of one adduct [MMP3–N-isobutyl-N-(4-methoxyphenylsulfonyl)glycyl hydroxamic acid] and then by calculating structural models of the other two adducts using a reduced set of experimental NMR data, following a recently proposed procedure (Bertini et al. in J. Med. Chem. 48:7544–7559, 2005). The inhibitors were selected with the criteria of maintaining in all of them the same zinc-coordinating moiety and of selectively changing the substituents and/or the functional groups. The backbone dynamics on various time scales have been characterized as well. The comparison among these structures and with others previously reported allowed us to elucidate fine details of inhibitor–receptor interactions and to develop some criteria, which could guide in optimizing the design of selective inhibitors. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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S-100 proteins represent a group of closely related acidic, calcium binding proteins originally isolated from the mammalian nervous system and later detected in non-neural cell types and in a wide variety of vertebrate and invertebrate species. The present study used immunochemical and immunohistochemical methods to extend the investigation of S-100 during phylogenesis to plant tissues. The presence of S-100-like immunoreactive material was detected in extracts of spinach (Spinacia oleracea L.) terminal buds and young leaves by the ELISA method and by Western blotting using different anti-S-100 rabbit antisera. Using the PAP method, serial sections of young spinach leaves treated with the same antisera exhibited an immunoreaction product that was confined to the cytoplasm and nucleus (but absent from the vacuoles) in meristematic, epidermal, and parenchymal cells. The present data enlarge the field of investigation of S-100 proteins in the search of the function(s) of S-100 in biological organisms.  相似文献   
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